#define  _CRT_SECURE_NO_WARNINGS 1
#include<stdio.h>
void Exchange(int*x, int*y)
{
	int z = *x;
	*x = *y;
	*y = z;
}

int main()
{
	int a = 10;
	int b = 20;
	Exchange(&a, &b);
	printf("a=%d b=%d", a, b);
	return 0;
}

